The present invention relates to new phenolic compounds derived from dialkoxyethanals, their preparation process and their application.
The benefit of the new phenolic compounds derived from dialkoxyethanals is twofold. First of all, new phenolic compounds with a protected aldehyde function can be obtained, which can be used as synthesis intermediates. Then, crosslinkers of phenolic type can be prepared but with the advantage that they do not release formaldehyde during their synthesis or their use. In order to have an idea of the benefit of such crosslinkers, reference may be made to the general article on phenolic resins, advanced in the Kirk-Othmer encyclopaedia, vol. 18, 4th edition, Wiley Interscience, 1996, p 603-644.
A subject of the present invention is thus new phenolic compounds derived from dialkoxyethanals of formula (I) 
in which
R is a dialkoxymethyl group with from 3 to 17 carbon atoms, a 1,3-dioxolan-2-yl group optionally substituted on peaks 4 and/or 5 by one or more alkyl groups comprising from 1 to 8 carbon atoms or a 1,3-dioxan-2-yl group optionally substituted on peaks 4 and/or 5 and/or 6 by one or more alkyl groups comprising from 1 to 8 carbon atoms.
n has the value 1, 2 or 3 and the group or groups 
are in ortho and/or in para position of the OH group of the cycle
m represents from 0 to 4-n and X represents a functional group such as hydroxyl or halogen such as chlorine, fluorine, bromine, iodine or an alkyl or alkoxy group comprising from 1 to 8 carbon atoms or aryl group comprising from 5 to 12 carbon atoms and optionally 1 or 2 heteroatoms such as nitrogen or oxygen or carboxy or xe2x80x94COxe2x80x94Y group in which Y represents an alkyl or alkoxy radical containing from 1 to 8 carbon or amido or amino or thiol radical, on condition that at least one of the ortho or para positions of the phenolic cycle is substituted by a hydrogen, with the exception of the compound 1 described by J. Gardent and J. Likforman, Recent Results Cancer Res. 1966, 22, 23-26. 
and their salts with the alkali metals, alkaline-earth metals and amines.
More particularly, a subject of the present invention is new phenolic compounds derived from dialkoxyethanals of formula (I) in which:
R is a dialkoxymethyl group comprising from 3 to 10, in particular 3 to 7 carbon atoms, preferably a dimethoxymethyl or diethoxyethyl group
n has the value 2 or preferably 1, the group 
being in ortho position or in para position of the OH group of the cycle,
m represents 0 or 1
X represents a hydroxyl or halogen group such as chlorine or an alkyl group such as methyl, ethyl or tert-butyl, or alkoxy group such as methoxy or ethoxy, or carboxyl group such as methyl carboxylate or ethyl carboxylate.
In other preferential conditions, when several groups X are present, they are identical. The alkyl groups comprising from 1 to 8 carbon atoms preferably contain from 1 to 5 carbon atoms, in particular from 1 to 3 carbon atoms.
In an even more particular manner, a subject of the present invention is new phenolic compounds derived from dialkoxyethanals of general formula (I) and more particularly the following compounds:
4-(1-hydroxy-2,2-dimethoxy-ethyl)-phenol
2-(1-hydroxy-2,2-dimethoxy-ethyl)-phenol
4-chloro-2-(1-hydroxy-2,2-dimethoxy-ethyl)-phenol
2-(1-hydroxy-2,2-dimethoxy-ethyl)4-methyl-phenol
4-tert-butyl-2-(1-hydroxy-2,2-dimethoxy-ethyl)-phenol
3-(1-hydroxy-2,2-dimethoxy-ethyl)4-hydroxy-methyl-benzoate.
A subject of the invention is also a preparation process for phenolic compounds derived from dialkoxyethanals of formula (I) and their salts with the alkali metals, alkaline-earth metals and amines characterized by the fact that, in the presence of a base:
a phenol of formula (II) 
in which R1, R2, R3, R4, R5 can be a hydroxyl radical, a halogen such as chlorine, fluorine, bromine, iodine or an alkyl radical comprising from 1 to 8 carbon atoms or an aryl radical or an alkoxy radical comprising from 1 to 8 carbon atoms or an ester radical comprising from 1 to 8 carbon atoms or an amide radical or an amine radical or a thiol radical, on condition that at least one of the ortho or para positions of the phenolic cycle is substituted by a hydrogen.
is reacted with an aldehyde of formula (III) 
in which R is a dialkoxymethyl group, a 1,3-dioxolan-2-yl group optionally substituted on peaks 4 and/or 5 by one or more alkyl groups or a 1,3-dioxan-2-yl group optionally substituted on peaks 4 and/or 5 and/or 6 by one or more alkyl groups in order to obtain the expected compound.
In preferential conditions of implementation of the invention, the phenolic compounds derived from dialkoxyethanals are prepared as follows: 0.1 to 10 moles of aldehyde of formula (III) and 0.1 to 2 base moles are introduced into a flask per 1 mole of phenol of formula (II). The whole is reacted at a given temperature for a given time. A crude reaction mixture is obtained of which the expected product or products are isolated if desired.
In other preferential conditions of the invention, 0.1 to 5 moles of aldehyde of formula III per 1 mole of phenol of formula 11 in the presence of 0.1 to 1 mole of base.
Still in other preferential conditions of the invention, the base necessary for the catalysis of the reaction can be a tertiary amine such as tributylamine or triethylamine or an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide, or an alkali metal carbonate such as sodium carbonate or potassium carbonate.
In yet other preferential conditions of the invention, the aldehyde of formula III can be dimethoxyacetaldehyde, diethoxyacetaldehyde, dibutoxyacetaldehyde, 2-formyl-1,3-dioxolane or 5,5-dimethyl 2-formyl 1,3-dioxane.
The phenolic compounds derived from dialkoxyethanals of formula (I) and their salts with the alkali metals, alkaline-earth metals and amines, subject of the invention, can advantageously be used as synthesis intermediates in pharmacy or in plant pharmacy. They can also serve for the preparation of phenolic resins without formaldehyde, the preparation of crosslinkers without formaldehyde of various substrates such as cellulose substrates, non-woven substrates, nylon, polyester, glass.
Finally, a subject of the present invention is the use of the phenolic compounds derived from dialkoxyethanals of general formula (I) and their salts with the alkali metals, alkaline-earth metals and amines, either as synthesis intermediate, or as intermediate for the preparation of phenolic resins without formaldehyde, or as crosslinker without formaldehyde with a substrate which can be a cellulose substrate, a non-woven substrate, of nylon, polyester or glass.
The following examples will allow the invention to be better understood.